20 numbers Biology 2016

 1. Bacteriophage T7 grown in a medium containing radioactive phosphorus will experience... A. its population decreases B. its DNA becomes radioactive C. its protein coat becomes radioactive D. it loses its ability to infect bacteria E. its DNA and protein coat become radioactive 

2. The following pair shows the origin and function of root hairs:... A. meristem – strengthens the plant B. epidermis – absorbs nutrients C. meristem – absorbs water D. meristem – absorbs nutrients E. epidermis – absorbs water 

3. Applying a wax coating to the skin of apples before they are marketed aims to... A. prevent bacterial contamination that damages the fruit B. make apples look beautiful and attractive C. prevent ethylene formation due to skin injury D. prevent aerobic respiration by controlling oxygen intake E. prevent sunlight from entering, which can change the color of apples 

4. What causes frog skin to turn pale in high light intensity conditions is... A. concentration of pigment in cells chromatophore B. accumulation of pigment in cells due to hormonal reactions C. pigment in cells does not absorb light D. pigment in cells spreads evenly due to heat E. pigment spreads in cells due to the influence of neurohormones 

5. In an experiment, a quantity of milk is poured into a beaker and then lactase enzyme is added. The enzymatic reaction results in... A. galactose concentration decreases, glucose concentration increases B. lactase concentration decreases, galactose concentration increases C. galactose concentration increases, lactase concentration remains the same D. lactose concentration increases, glucose concentration remains the same E. glucose concentration decreases, galactose concentration increases 

6. Based on Darwin's theory of evolution, the reason turtles of the same species have morphological differences is isolation... A. behavior B. reproduction C. geography D. mechanical E. seasons 

7. Scale color in fish species is inherited through a single gene with four different alleles. The number of gametes that determine scale color that can be produced is... A. 1 B. 2 C. 4 D. 8 E. 16 

8. Fats are oxidized in the cytosol through the beta- oxidation cycle. CAUSE Acetyl-CoA is a product of the beta- oxidation process. The answer is D.

9. Fasciola hepatica is a parasitic worm in sheep. REASON Fasciola hepatica lives and reproduces in the liver of sheep. The answer is A 

10. In Porifera, O2 binding and CO2 release are carried out by choanocytes directly adjacent to the spongocoel cavity. REASON Porifera take in water through the ostia, then enter the spongocoel cavity. The answer is D 

11. Plastids are plant cell organelles specialized for storing starch. REASON Plastids are plant cell organelles that contain chlorophyll. The answer is E 

12. In amoeba, lysosomes are located within the food vacuole. REASON Lysosomes function to digest food within the food vacuole. The answer is D 

13. Plant tissue culture techniques are often used for plants that are difficult to propagate vegetatively. WHY Plant tissue culture techniques are used to produce uniform seedlings based on the totipotency of plant cells. The answer is A 

14. The biomass pyramid in aquatic ecosystems is the opposite of that in terrestrial ecosystems. WHY The average mass of producers in water is smaller than the average mass of consumers. The answer is B 

15. In each DNA molecule, the number of adenine bases is equal to the number of thymine bases. WHY The four nitrogenous bases that make up nucleotides in DNA are equal in number. The answer is C

16. Bats and whales share characteristics in that they have... (1) mammary glands (2) placenta (3) echolocation (4) rudimentary hind legs The answer is A 

17. Homeostasis in the human body is controlled by the... system (1) nervous (2) circulatory (3) endocrine (4) digestive The answer is B 

18. Intraspecific competition can be reduced if... (1) offspring are evenly distributed (2) parents and offspring have different niches (3) each individual defends its territory (4) the environmental carrying capacity exceeds the number of individuals The answer is C 

19. The following graph illustrates the relationship between factors that influence enzyme activity and reaction speed:... (1) (2) (3) (4) The answer is A 

20. The life cycles of mosses and ferns are similar in that... (1) they produce spores (2) experiencing alternation of generations (3) the gametophyte generation produces sperm and egg cells (4) the gametophyte generation is a heterotrophic individual The answer is A